Value default initializer. (#9681)

Summary: #8364

Differential Revision: D71913869

---------

Co-authored-by: Anthony Shoumikhin <[email protected]>

Author: kirklandsign

extension/apple/ExecuTorch/Exported/ExecuTorchValue.h

@@ -30,10 +30,30 @@ typedef NS_ENUM(uint32_t, ExecuTorchValueTag) {
   ExecuTorchValueTagOptionalTensorList,
 } NS_SWIFT_NAME(ValueTag);
 
+/**
+ * A dynamic value type used by ExecuTorch.
+ *
+ * ExecuTorchValue encapsulates a value that may be of various types such as
+ * a tensor or a scalar. The value’s type is indicated by its tag.
+ */
 NS_SWIFT_NAME(Value)
 __attribute__((deprecated("This API is experimental.")))
 @interface ExecuTorchValue : NSObject
 
+/**
+ * The tag that indicates the dynamic type of the value.
+ *
+ * @return An ExecuTorchValueTag value.
+ */
+@property(nonatomic, readonly) ExecuTorchValueTag tag;
+
+/**
+ * Returns YES if the value is of type None.
+ *
+ * @return A BOOL indicating whether the value is None.
+ */
+@property(nonatomic, readonly) BOOL isNone;
+
 @end
 
 NS_ASSUME_NONNULL_END

extension/apple/ExecuTorch/Exported/ExecuTorchValue.m

@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#import "ExecuTorchValue.h"
+
+@interface ExecuTorchValue ()
+
+- (instancetype)initWithTag:(ExecuTorchValueTag)tag
+                      value:(nullable id)value NS_DESIGNATED_INITIALIZER;
+
+@end
+
+@implementation ExecuTorchValue {
+  ExecuTorchValueTag _tag;
+  id _value;
+}
+
+- (instancetype)init {
+  return [self initWithTag:ExecuTorchValueTagNone value:nil];
+}
+
+- (instancetype)initWithTag:(ExecuTorchValueTag)tag
+                      value:(nullable id)value {
+  if (self = [super init]) {
+    _tag = tag;
+    _value = value;
+  }
+  return self;
+}
+
+- (ExecuTorchValueTag)tag {
+  return _tag;
+}
+
+- (BOOL)isNone {
+  return _tag == ExecuTorchValueTagNone;
+}
+
+@end

extension/apple/ExecuTorch/Exported/ExecuTorchValue.mm

@@ -11,6 +11,8 @@
 import XCTest
 
 class ValueTest: XCTestCase {
-  func test() {
+  func testNone() {
+    let value = Value()
+    XCTAssertTrue(value.isNone)
   }
 }